(1) Field
Exemplary embodiments of the invention relate to a touch screen panel, a touch sensing apparatus including the touch screen panel. More particularly, exemplary embodiments of the invention relate to a touch screen panel with improved touch response speed and a touch sensing apparatus including the touch screen panel.
(2) Description of the Related Art
Various types of input devices are presently available for performing operations in a computing system, such as buttons or keys, mice, trackballs, touch sensor panels, joysticks, touch screens and the like. Touch screens, in particular, are becoming widely used because of ease and versatility of operation and declining price thereof. Touch screens may include a touch sensor panel, which may be a transparent with a touch-sensitive surface. The touch sensor panel may be positioned in front of a display screen so that the touch-sensitive surface covers the viewable area of the display screen.
Touch screens may allow a user to make selections and move a cursor by simply touching the display screen via a finger or stylus. In general, the touch screen may recognize the touch and position of the touch on the display screen, and the computing system may interpret the touch and thereafter perform an operation based on the touch event.
Touch sensor panels may be implemented as an array of pixels defined by multiple drive lines (e.g., rows) crossing over multiple sense lines (e.g., columns), where the drive and sense lines are separated by a dielectric material. In some touch sensor panels, the row and column lines may be provided on a single side of a substrate. In such touch sensor panels, both near and far electric field lines are coupled between the row and column lines of each pixel, with some of the far-field lines passing through and temporarily exiting the cover glass protecting the drive and sense lines.
When the driving line or the sensing line is configured by plural pads, routers are connected to corresponding pads. For example, a router (e.g., a driving router) connected to a driving pad transmits a touch pulse provided from an external device to a corresponding driving pad, and a router (e.g., a sensing router) connected to a sensing pad transmits a sensing signal sensed through a corresponding sensing pad to the external device.
However, as a resolution of a touch panel is increased, the number of the routers increases such that an interval between router lines decreases, and a parasitic capacitance is thereby increased.
Moreover, as the number of routers is increased, resistive-capacitive (“RC”) delay by router lines occurs such that a touch response time increases.